Apparatus for burning fuel



June i4, 1932. .1.V MA SCHUTZ 1,862,910 l APPARATUS FOR BURNING FUEL i? w 9 .jsef/JSk/wk y A afm' June 14, 1932. A J. M. scHUTz 1,862,916

APPARATUS FOR BURNING FUEL Filed June 7. 1929 5 Sheets-Sheet 2 June 14, 1932. L M. SCHUTZ l 1,862,910

APPARATUS FOR BURNING FUEL 'Filed June '7, 1929 5 Sheets-Sheet 3 June 14, 1932. M' SCHUTZ 1,862,910

APPARATUS' FOR BURNING FUEL n Filed June 7. 1929 5 Sheets-Sheet 4 dbtoz nu,

'im l June 14, 1932. J. M. scHuTz 1,862,910

" APPARATUS FOR BURNING FUEL Filed June 7. 1929 5 sheets-sheet` '5 l l y f5? E916: imi y rwantoz .Jan/U1. ,sz/wiz vsumed.

A further object is to provide a fuel burn 'Patented June` 14, 1932 UNITED STAT-Es JOSEPH- MARTIN SCHUTZ, 0F NASHVILLE,

'I PATENT OFFICE TENNESSEE, SSIGNOE To THE mmm' COMBUSTION ENGINEERING- CO., 0F NASHVILLE TENNESSEE, A CORPORATION OI' TENNESSEE APPARATUS FOR BURNING FUEL Application led il'une ll, 1929. Serial No. 369,069.

My present invention relates to apparatus for burning fuel, and particularly to an apparatus intended for use in burning liquid fuel in the presence of pressure air to attain -a high heating efficiency.

An object of this invention is to provide an apparatus including a fuel burner made entirely of metal to be placed within a furnace or heating chamber where it will be subjected nation of any foreign matter or products of.

combustion, thus keeping the apparatus at all times in condition to carry out the process ofv complete and efficient combustion with highest efiiciency and a maximum'generation of usable B. t. u. for the amount of fuel coner having a gas generating chamber constricted at its outlet and havine` the air inlet opening thereinto at an angle tfrom a radial line whereby fuel and air supplied through the inlet will be circulatedfwithin the generating chamber to break up the fuel to combine 'with the air following which it emerges at the outlet, and a casing member fitted concentrically at the outlet lof the gas generating chamber and provided with air inlet passages for introduction'of augmenting air to unite with the emerging gas to form a combustible mixture.

Still another object is to provide for the burning of fuel in accordance with my invention which consists in injecting a Stream of fuel and air for decomposing the same into a gas producing chamber to there be sufiiciently confined to circulate for a period suiiicient for decomposition of the fuel, ankd to then emerge in a gaseous stream toward a burner, and positively introducing additional air into the gas to attain substantially perfect combustion proportions as the/burner is reached.

A further object is to rovide a burner comprisin a burner annu us closed at one end and ared toward an open combustion end, said burner annulus being rovided with a fuel inlet at the closed end an having multiple air inlets along lthe eXtentof` the ared portion of increased capacity toward the combustion end.

Yet'another object is to provide a burner housing which takes heat from the combustion of the fuel to maintain a proper operating temperature for most ef'cient volatization of the fuel and completecombustion at the burner opening, and whichcontemplates the use of air to cool the parts to prevent overheating and with subsequent use of air thus heated to support combustion and conequently increase the heating eiiiciency of the urner.

Another object is to provide an appagatus including a system white has means forinitial forming and ignition of the fuel supply.

until the apparatus is suiiciently heated for self-generation and ignition, and in providing for automatically cutting out this initlal operating means when full operation. is attained, and in fact'for complete automatic control of the a paratus when in use.

Another ob]ect resides in providing al mechanism of such character that excess ,oil supplied to the burner will be pumped back to the source of supply, and all the oil will be returned back in case the ignition does not function, thus eliminating the possibility of oil iioodlng and the consequent dangers of fire and explosions. e A

Another object lies in so, constructing the burner mechanism that a vortex is created in the gas forming chamber to set up a whirling and mixing action to secure proper volatilization of the fuel.

An additional object is to provide a burner structure which is scientifically proportioned for progressive expansion and addition and combination of air to attain a theoretically perfect combustible mixture at the flame point.

Still another purpose of this invention is to provide a burner structure having the inlets thereof'arranged to maintain substantially constant and uniform whirling expansion and mixing circulation in all parts of the volume of mixture as the gas travels to- Wards and is supplied to the flame.

A still further purpose lies in providing a metering or oil control mechanism which insures a metered and regulated supply of oil Which is self cleaning, and which can be set to suit different characters of fuel and different operating conditions.

With the above and other objects in View which will be apparent to those skilled in the art, my invention includes certain novel features of construction, combinations and assemblies of parts, and processes and steps which will be hereinafter set forth in connection with the drawingsand then pointed out in the claims.

In the drawings:

Figure 1 is a view in top plan of an apparatus constructed in accordance with my invention.

Fig. 2 is a view in side elevation of the apparatus with portions in section to better illustrate the construction and arrangement of the parts.

Fig. 3 is a horizontal sectional view through the burner substantially on line 3 3 of Fig. 5.

Fig. 4 is a horizontal sectional View on line 4--4 of Fig. 5.

Fig. 5 is avertical sectional view on line 5 5 of Fig. 3.

Fig. 6 is a view in perspective showing one of the tuyre rings.

Fig. 7 is a detail sectional view showing the fitting of a pair of tuyre rings.

A' Fig. 8 is a fragmentary View in bottom plan of one of the tuyre rings.

Fig. 9 is a fragmentary detail view, partly 1n section, on line 9- -9 of Fig. 10, showing the metering or oil control device.

Fig. 1() is a sectional View on line 10-10 of Fig. 9.

Fig. 11 is a fragmentary detail sectional View to better show the fluid oil control valve.

Fig. 12 is a sectional view on line 12-12 of Fig. 9.

Fig. 13 is a view in top plan of the fluid fuelpump. l

Fig. 14 is a vertical sectional view substantially on line 14 -14 of Fig. 13.

Fig. 15 is a vertical sectional view on' line 15-15 of Fig. 1a y Fig. 16 is a sectional view taken vertically on line 16-16 of Fig. 18.

Fig. 17 is a fragmentary view to. better show thek arrangement of the liquid fuel supply control.

Fig. 18 is a diagrammatic view illustrating an electric and thermal control system particularly adapted for my apparatus.

Fig. 19 is a vertical sectional View similar to Fig. 5 showing a modified form of burner.

Fig. 20 is a transverse vertical sectional View showing another modified construction.

In the present instance I have illustrated my improved apparatus as adapted for the burning of oil or liquid fuels, but as the description progresses it will be apparent that the apparatus might be well adapted for burning of powdered or comminuted fuels, with slight variations.

I have here shown a burner structure of the type which might be applied for use in conjunction with domestic furnaces or heat ing boilers of the steam, vapor or hot water types, and the mechanism is so constructed, arranged, and assembled, thatthe burner portion will be located in the fire box or other suitable porti-on of the heating plant and the operating mechanism will be located outside of the heating plant. The burner structure, generally indicated at A, is supplied with oil or other liquid fuel from a pump generally indicated at B, air being supplied under pressure by blower C. The supply of oil is controlled by a metering device D, initial ignition being accomplished through an arrangement of firing plugs at E. While the metering device is indicated to take care of and substantiallyprevent excess supply of oil or fuel, an oil return F is provided for safety in case of improper functioning andv the pump B also functions to return the excess oil to the supply. In order that the o eration of my improved apparatus may e automatic, it is preferable that a complete electrical or other'control be provided, and one form of such a control'apparatus will be set forth more in detail as the description progresses. e

The burner has an annular rim or case 1 formed on two diameters to provide an air chamber 2 and a restricted gas generating chamber 3, with a shoulder 4 between the tWo chambers'. The gas generating chamber 3 has the bottom thereof raised in a substantially flat conical form toward the center, and an injection opening 5 is provided at the center, which would be the apex of the flattened conical bottom. A ring plate 6 is fitted in the shoulder l to form a crowned up top for the gas generating chamber with a restricted v central opening through which the expandthe upper edge of the burner case 1 and against the upper tuyre ring 9 to thus form al top for air chamber 2. A baiiie ring 12 is located in the air chamber 2 with its lower edge bearing upon the ring plate 6 and its.

upper edge terminating short of contact with the burner ring 11 to thus leave an air passage over the top of the plate.

A main air supply duct 13 leads to theair chamber 2 to open tangentially thereinto as best shown in Fig. 1., and air supplied under pressure through this air duct to air charnber 2 will flow over the top of the baiiie ring 12 and then thro-ugh the air injection openings 14 of the tuyere rings. As bestshown in Figs. 3 and 6, the air injection openings 14 are formed through the tuyre rings to inject air into the burner annulus in substantially tangential jets or-streams so that a whirling motion will be maintained, thus causing circulation and agitation of the augmenting air an'd the gas expanding through opening 10. As the burner annulus is of substantially spread or tapered form from the opening 10 Ito the burner ring 11, the gas and air are permitted greater room for expansion and, in line with my purpose to secure Vas nearly a perfect mixture as possible at the ame point within the burner ring, I increase the collective area .of the. augmenting air injection passages in the several tuyre rings progressively from the opening 10 toward the burner ring 11, thus increasing the supply of auginenting air as the mixture is circulated and 1s better prepared to take up the air and mix the same'with the expanding gas.

A firing tube 15 leads tothe gas generating chamber .3 and opens thereinto tangentially. Thus, as a rich mixture is supplied through this firing tube to discharge into the generating chamber, the mixture will be whirled within the generating chamber and hea-vier particles will be, carried out by centrifugal force to Contact with the side walls of the generating chamber.

ratus and in carrying out my improved.

In the use of my 'appamethod, liquid fuel and a volume of air suiiicient to decompose the same into a rich' gaseous mixture will be supplied thro-ugh firlng tube 15 and particles ofthe liquid fuel willbe carried out to contact with the wall of the chamber 3, the mixed air and rich gas being caught in a vortex in the center of the generating chamber and expanding up through the opening 10. On the lower side of the burner case l I mount an oil return and auxiliary air supply case 16 having a central opening and passage registering with the opening 5 in the bottom of the generating chamber 3. An air duct 17 leads from air chamber 2 to an annula'r duct 18 in this auxiliary case 16. The annular duct 18 is around the central opening 5 and an air supply ring 19 is located adjacent the annular duct 18 and is provided with tangential air supply Y openings 20 so that air will be injected at the hopening 5 with a whirling force to rise through the center of the generating chamber and aid inthe agitation and breaking down of the charge within thegenerating chamber to secure a better mixture of the rich gas, rising through opening 10. This action may be still further aided by providing a passage 2l in the case 16opening at one end in line with opening 5 andmhaving its lremaining end registering with passage 22 leading laterally from the generating chamber. As

the mixture is circulated and whirled within the generating chamber 3, a portion of the rich gas will find its way through passages 22 and 2l to be discharged vertically up through opening 5 in the bottom of the generating chamber, and at the same time this stream of gas injected centrally into the generating chamber will be subject to the stirring and augmenting influences of the air injected tangentiallythrough the openings 20. An o-il 'return pipe 23 is connected with passage 21,

and any excess quantity of oil 4accumulating in the generating chamber 3 will drain through the passage 21 into this pipe 23. Further, .if the burner should cease to function properly through the flame or firing mechanism being extinguished, or for any 'other cause, all danger of flooding, explosions or fire will be eliminated as the excess l oil will be drained off through pi e 23.

'This burner structure might e mounted on a suitable' base 24. or can be otherwise supported or mounted within the tire box or other appropriate part of the furnace or heating plant, and to facilitate installation it is preferable that the main air duct 13, the firing tube 15, and the oil return pipe 23 be each provided with a union o r other readily v detachable connection at its outer-end.

The blower C is connected with a valve box 25, and this valve box is in turn4 connected with the main air duct 13 by a union or other readily'deta'chable coupling. A flap valve 26 is mounted at the end of the valve box 25 nearest the blower C to close by gravity and to be opened by the air pressure. n. arm 27 on .the pivot shaft of this fiap valve 26 is adapted to engage with an adjustable stop 28 which can be manually set to limit the def gree of opening of thevalve 26. This valve .j

will be opened by the air pressure,during normal operationA of the burner but will swing' down to a closed position when the blower C ceases to operate.

A firing plug casev 29 is connected by" coupling 30 with the firing tube 15, andthis firing plug case 29 has an air pipe 31 leading laterally therefrom to connect with the valve box 25, a butterfiy valve 32 being mounted in this pipe 31 to permit manual control and regulation ofthe amount of air supplied from the valve box through pipe 31, firing plug case 29 and consequently to the firing tube 15. The firing plug arrangement, as best shown in Fig. 12, consists of the two insulated plugs 33 and 34 mounted in suitable openings in the case structure 29, and these plugs carry ele'ctrodes 35 and 36 which have their inner ends extended to terminate in the middle of the case 29, the electrodes being spaced to form a gap so that when high tension-current is passed Vthrough the electrodes a spark will jump the gap. A branch air pipe 37 has ducts 38 and 39 opening adjacent the firing plugs, to blow air around the same to prevent overheating and to guard 'against accumulation of carbon, or other matter which might foul the plugs. i

An oil supply nozzle 40 projects into the firing plug casing 29 at a point substantially in axial alinement with the firing tube 15, and a jet fixture 41 is provided so that oil sprayed from said nozzle will be discharged in a fine mist adjacent the electrodes 35 and 36. The oil pump B is adapted to supply oil under pressure to thenozzle 40 through pipe 42, but it is desirable that means be provided to regulate andv govern the pressure at which the oil is injected through the spray fitting 41, and to so arrange the parts that when they pump is not in o eration the spray fitting will be closed. Wit i this in mind I provide a cylindrical bore Within the nozzle 40 and mount therein a plunger 43 having a grooved portion 44 adapted to slide within the cylindrical bore and a needlepoint 45 to close in the inner end of the opening of the spray fitting 41. An oil metering casing 46 is provided around the outer .end of the nozzle 40 and has an oil reserve chamber 47 therein with which the oil supply pipe 42 connects to supply oil under pressure from oil pump B. A diaphragm 48 is mounted on the outer end of the plunger rod 43 and is positioned to be influenced by the oil pressure Within the chamber 47 to withdraw the plunger rod suiiiciently to unseat the needlepoint 45 from the opening of the spray fixture 41. This diaphragm 48 is held in place by a cap 49 which has a coil spring 50 fitted therein to bear against the outer side of the diaphragm. A pressure washer 51 1s 1n contact with the other end of spring 50 and an adjusting screw 52VV is fitted through a threaded opening in the cap 49 to bear against this pressure washer 51.

With this arrangement it .is possible to vary the resilient pressure exerted by spring 50 through adjustment of screw 52, to thus vary the pressure required upon diaphragm 48 to move the plunger rod 43 to open the spray tting.` A coil spring 53 is provided around the lunger rod 43 on the inner side of the diap iragm to make the action of the same stable. A pressure gauge 54 is connected in connection with chamber 47 to give visible readings of the pressure of the oil therein.

As better shown in Fig. 10, a blow-oli opening 55 is provided from the oil chamber 47 and an oil return pipe 56 is connected therewith. A plunger rod 57, serving as a blow-oli valve, has a needlepoint 58'Working adjacent an opening 59 establishing communication to this blow-off passage 55. A diaphragm 60 held in place in cap 61 is connected with the other end of the plunger 57 to be influenced by the pressure ofvfuel oil within chamber 47 to move the plunger rod sufficiently to unseat the needlepoint 58 from the passage or opening 59. A coil spring 62 is fitted Within the cap 61 to bear at one end against the diaphragm and this coil spring bears at its remaining end at pressure nut 63, which is adjusted through adjusting screw 64. A coil spring 65 is provided around the plunger rod 57 on the opposite side of the diaphragm 60. W'ith this arrangement of the parts it is possible to manually adjust the resilient pressure exerted by spring 62 upon diaphragm 60 to hold the needlepoint 58 in the closed position, and such adjustments will consequently vary the blow-ofi' pressure required within the chamber 47 to Work against the diaphragm 60 and move plunger rod 57 to open the passage 59 to the blow-ofi". With this arrangement, it is possible to regulate and vary the pressure and the amount of oil supplied through the spray fitting 41, and the pressure gauge 54 Will give visible indications to permit accurate and precise manual settings for most elicient operation.

The pump B,as better shown in Figs. 13 to 16, inclusive, is of the direct drive gear type, and is constructed to have high and low pressure sides for pumping oil under pressure and for returning oil coming lfrom the metering device D and excess or dripping oil Which may be caught in the generating chamber, and this pump mechanism is so arranged that leakage of oil on the high pressure side is-positively precluded.

The pump B andblower C are operated by an electric motor 66, the shaft 67 of the pump and shaft 68 of the blower being directly connected with the motor shaft 69.

The pump case 70 has heads 71 and 7 2 bolted or otherwise rigidly secured thereto on the high and low pressure sides respectively, and adjacentthese heads the ease is chambered at 73 and 74 to receive the pump gears 75 and 76 for the high pressure si de and pump gears 77 and 78 for the low pressure side. The head 72 on the low pressure side has a bearing opening 79 to receive and journal the pump shaft 67, and head 71 has an alined opening internally screw-threaded to receive a bearing cap 80 which journals the end of lll) - gears 75 and 77 are keyed' or otherwise secured to the shaft 67, and pumpgears 76 and 78 are carried by a shaft 81 mounted in a Y suitable opening provided in the pump case 70. A groove is provided at 81 around the pump shaft 67 at the low pressureside to prevent escape of oil through the bearing 79, and discharges back to the intake side of the Pump' Oil supply pipe 82 leading from a tank or other suitable source of supply of oil is connected with the pump casingv head 71 and oil pipe 42 leads from the high pressure side.

eturn oil pipe 83 connects with the intake on the low pressure side and a pipe 84 leads from the low pressure outlet to discharge into the tank or other receptacle where the excess oil:

shaft bearing, but this will only serve to lubricate the shafts and this leaking oil will be immediately taken care of on the low pressure side to be returned through discharge pipe 84.

An oil sump 85 has a circuitous path or passage to form a trap, and the oil return pipe 23 from the generating chamber isconnected with one end of this oil sump adjacent the top 'through the use of a union 86, or other suitable coupling. The pipe 83 connects with the opposite end of the oil sump adjacent the bottom, and excess oil pipe 56 connects with this return pipe 83.

It isvpreferable that an electromagnetically operated valve 87, the construction of which is best shown in Fig. 17, be connected in the oil pipe 82 from the oil supply tank, or other source of supply, this valve to be normallyclosed when the electromagnetic means is deenergized. In Fig. 18 I have illustrated diagrammatically-a control system which might be employed to advantage in the use of my improved apparatus. As shown, the valve 87 and themotor 66 are included in the same general electric., wiring circuit controlled by switch 88-,and receiving energy from a storage battery 89, or other suitable source of supply. This same circuit also di` rectly connects with thel firing plug mechanism at E, a spark coil or other high tesion transformer mechanism being introduced at 90 into this circuit to` give .the desired ino tensity of the spark. A room temperature thermostat 91, adapted to be located in a liv ing room or other space to be heated is connected in the general circuit and when tne maximum temperature as set at this room thermostat is reached, the circuit will be it is the intention that the liquid fuel shall be.

introduced into the gas generating chamber with substantially only one-fourth of the air required to give a theoretically perfect combustible gas, and as the gas rises through the burner annulus each of the tuyre rings 7, 8 and 9 will successively supply an additional one-fourth of the re uired air, until the full amount of air has een s uppliedand has beenuagitated with the initial gas mixture before the point of combustion is reached, at the burner ring l1. It has been found that a much better mixture of air and hydrocarbons is obtained by this proportionate and successive introduction of augmenting air as the gas volume is permitted to expand in the upwardly tapered or flared burner annulus, and when the point of full combustion is reached at the burner ring 11, the whirling mass of gas will burn with a low flat radiant flame.

As shown in Figs. 19 and 20, a greater or less number. of tuyre rings might be employed to suit different or particular conditions of operation and use.

In carrying out the process of burning fuel cellent advantage as the fuel is supplied in a stream so directed as to allow for progressive expansion, and augmenting air is introduced -v in increasing volume during the progress of the' stream to lattain substantially erfect combustion proportions as the com ustion point is reached.

While I have herein shown and described only certain specific embodiments of my invention, certain possible mechanical constructions and combinations, andcertain `steps in the .carrying out of the process or method, 1t

will. be appreciated that many changes and variations can be resorted to without departing from the spirit and scope of my invention. v

I claim:

1. A fuel burner comprising a gas generating chamber having a restricted outlet and an inlet opening `thereinto .at an angle from a radial line, means to inject fuel through the inlet opening in a blast tangentially into the .generator chamber to circulate therein and escape through the outlet, aburner annuus tted concentricallyaround the restricted outlet of the gas generating chamber and provided with tangential air inlet passages, and means to introduce air under pressure in alstream substantially axially through said.

through the inlet opening in a blast tangentially into the generator chamber to circulate therein and escape through the outlet, a burner annulus fitted concentrically around the restricted outlet of the gas generating chainber and provided with tangential air inlet passages, means to introduce air under pressure in a stream substantially axially through said generating chamber and the outlet thereof, and means to intro-duce air under pressure through said-air inlet passages.

3. A fuel burner comprising a gas generating chamber restricted at its outlet and having an inlet opening thereinto at an angle from a radial line, tangentially opening tuyre means to create 'a vortex at a point opposite the outlet Vand traveling toward the same, and a burner annulus fitted concentrically at the outlet of the gas generating chamber and provided with air inlet passages along the extent thereof. v

4. A fuel burner comprising a gas generating chamber restricted at its outlet and havingv an inlet opening thereinto at an angle from a radial line, tangentiallyy opening tuyre means to create a vortex at a point opposite the outlet and traveling toward the same, a burner annulus fitted concentrically at the outlet'of the gas generating chamber and provided with air inlet passages along the extent thereof, and means to introduce air through said inlet passages tangentially in line with the vortex.

5. A fuel burner comprising a gas generating chamber restricted'at its outlet and having an inlet opening thereinto at an angle from a radial line, tangentially opening tuyre means to create a vortex at a point opposite the outlet and traveling toward the same, a burner annulus fitted concentrically at the outlet of the gas generating chamber and provided with air inlet passages alone' the extent thereof, means to introduce air t rough said inlet passages tangentially inline with the vortex, and means to introduce air under pressure into the generating chamber axially in line with the outlet openy ing:

6. A fuel burner comprising a gas generatino` chamber of annular form having a restricted outlet opening substantially axially and having an inlet opening through the side wall at an angle from a radial line,a burner .annulus fitted concentrically around'the restricted outlet and flared toward an open combustion end, said burner annulus being provided with multiple air inlets opening tangentially along the extent of the flared portion and of progressively increased capacity toward the combustion end, means to introduce fuel through the inlet to escape as a rich gas through the restricted outlet, means to introduce air under pressure through the inlet passages of the' burner annulus to combine with the rich gas `and form a substantially perfect mixture at the combustion if end, and tangentially opening tuyre means to circulate gas within the generating chamber and create a vortex traveling toward the outlet.

7. A fuel burner comprising a gas generating chamber of annular form having a restricted outlet opening substantially axially and having an inlet opening through the side Wall at an angle from a radial line, a burner annulus fitted concentrically around the restricted outlet and flared toward an open coinbustion end, said burner annulus being provided with multiple air inlets opening tangentially along the extent of the flared portion and of progressively increased capacity toward the combustion end, means to introduce fuel through the inlet to escape as a rich gas through the restricted outlet, means to introduce air under pressure through the inlet'I passages of the burner annulus to combine With the rich gas and form a substantially perfect mixture at the combustion end, tangentially opening tuyre means to circulate gas within the generating chamber and create a vortex traveling toward the outlet, and means to introduce a limited quantity of pressure air substantially axially into the generating chamber.

8. An apparatus for burning fuel comprising a burner having a gas generating chamber and provided with a flared burner annulus having tangential air4 passages opening through the sides thereof, a firing tube connecting with the generating chamber, a main air duct to supply air through the tangential air passages, a liquidfuel spray nozzle, positioned to discharge substantially centrally into the firing tube, a blower to supply air through the main air duct and a limited quantity of air through the firing tube to mix with the spray from the nozzle, a pump to supply liquid fuel to said nozzle, firing plugs having their firing points substantially in the path of the spray from said nozzle, electrically actuated means to operate the blower and the fuel pump, an electromagneticallyopened valve'normally closing the fuel supply to the pump, and an electric circuity connecting the firing plugs and the electrically actuated and operated means.

9. An apparatus for burning fuel comprising a burner having a gas generating chamber and provided with a flared burner annulus having tangential air passages opening through the sides thereof,'a firing tube connecting with the generating chamber, a main air duct tosupply air through the tangential air passages, a liquid fuel spray nozzle, positioned to discharge substantially centrally into the firing tube, a blower to supply air through the niain air duct and a limited quantity of air through the firing tube to mix with the spray from the nozzle, a pump to supply liquid fuel to said nozzle, firing plugs having their firing points substantially in the path of the spray from said nozzle, electrically actuated means to operatethe blower and the fuel pump, an electromagnetically opened valve normally closing the fuel supply to the pump, an electric circuit connecting the firing plugs and .the electrically actuated and operated means, and means to control the circuit connections.

10. An apparatus for burning fuel comprisl ing a burner having a gas generating chamber and provided with a flared burner annulus having tangential air passages opening throughthe sides thereof, a irin tube connectingwith the generating cham er, a mam air duct to supply air through the tangential air passages, a liquid fuel spray nozzle, ositioned to discharge substantially centra y into the firing tube, a blower to supply air through the main air duct and a limited quantity of air through the firing tube to mix with the spray from the nozzle, a pump to supply liquid fuel to said nozzle, firing plugs having their ring points substantially in the path of the spray from said nozzle, electrically actuated means to operate the blower and the fuel pump, an electromagnetically opened valve normally closing the fuel supply to the pump, an electric circuit connecting the firing plugs and the electrically actuated and operated means, a return pipe to drain excess liquid fuel from the gas generating chamber, a sump to collect the excess liquid fuel, and a return connection from said sump to the fluid pump.

11.' An apparatus for burning fuel comprising a burner having a gas generating chamber and provided with a flared burner annulus having tangential air passages opening through the sides thereof, a iirino' tube connecting with the generating chamier, a main air duct to supply air through the tangential air passages, a liquid fuel spray nozzle, positioned .to discharge substantially centrally into the firing tube, a blower to supply air through the main air duct and a limited quantity of air through the firing tube to mix with the spray from the nozzle, a pum to supply liquid fuel to said nozzle, tiring p ugs having their firing points substantially in the path of the spray from said nozzle, electrically actuated means to operate said blower and said pump, a valve normally closing the liquid supply to the pump and electrically actuated to open the supply, electric circuit connections to said electrically actuated portions and the firing plugs, means to control said circuit, and avalve to close said main gentiall into the air chamber, a ring plate mounte at said shoulder to form a restricted gas outlet opening from said generating chamber, a plurality of tuyre rings of successively increased diameter and having tangential air passages through the side wall thereof mounted concentrically one upon the other to be supported by the ring plate around the gas discharge opening for the generating chamber, a burner ring mounted on the uppermost tuyre ring and the upper edge of the casing to close the air chamber, a baiie ring mounted on the ring 'plate within the air chamber, means to introduce liqgenerating chamber, an air duct openingtangentially into the air chamber, a ring plate mounted at said shoulder to form a restricted gas outlet opening from said generating chamber,`a plurality of tuyre rings of successively increased diameter and having tangential air passages through the side Wall thereof mounted concentrically one upon the other to be supported by the ring platearound the gas discharge opening for the generating chamber, a burnerring mounted on the uppermost tuyre ring and the upper edge of the casing to close the air chamber, a baffle ring mounted on the ring plate within the air chamber, 'means to introduce liquid fuel through the firing tube," means to introduce air through the air duct and in limited quantities through the firing tube, said casing having an opening through the bottom of the gas generating chamber through Which excess oil may pass, and means to introduce augmentling air through this bottom opening.

14. An oil burner comprising a burner casing having an air chamber in the u per portion thereof and a generating chamger in the lower portion, with a shoulder intermediate, a firing tube opening tangentially into the generating chamber, an air ductopening tangentially into the air chamber, a ring plate mounted at said shoulder to form a restricted gas outlet opening from said generating chamber, a plurality of tuyre rings of successively increased diameter and having tangential air passages Athrough the side Wall thereof `mounted concentrically one upon the other to be supported by the ring plate around the gas discharge opening for the generating chamber, a burner ring mounted on the uppermost tuyre ring and the upper edge of the casing to close theair chamber, a baffle ring mounted-on the ring `plate within the air chamber, means to introduce liquid fuel through tliering tube, means to introduce air through .the air duct and in limited quantities through the ring tube, said casing having an opening through the bottom of the gas generating chamber through which excess oil may pass, means to introduce augmenting air through this bottom opening, and means to return excess oil which may pass through the bottom opening.

In testimony whereof I hereunto affix my signature.

JOSEPH MARTIN SCHUTZ. 

